(a) Field of the Invention
The present invention relates to a power supply.
(b) Description of the Related Art
A triac dimmer passes each cycle of a sine wave of an AC input by a dimming angle. The input voltage is cut off by the dimmer, and a period during which the input voltage is generated.
A power supply including a dimmer includes a main switch that controls power supply. A conventional power supply switches the main switch even in the period during which no input voltage is generated.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.